Dear Cody,
These are Barklice or Tree Cattle. They are benign creatures that do not harm the tree as they feed on lichens that frequently grow on older trees. Your image contains mostly striped nymphs, though if you look closely, you will see a few winged adults.

Subject: Unknown group of bugs
Location: Coastal NC
May 28, 2016 4:55 am
We live on the mainland of Holden Beach, NC. I have never seen this bug but all of a sudden this week I have noticed several clusters of bugs on several of my live oak trees. It is May 28th.
Please help me to identify these creatures. Some clusters are smaller than others. Do I need an exterminator and will they destroy my trees? Some of these clusters are like 8×8 inches. This is creeping me out, I’m not a bug lover, just a bird lover, but yet I havent seen any birds eating them. I wish they would.
Thank you!
Signature: Loretta

Tree Cattle

Dear Loretta,
These benign Barklice are sometimes called Tree Cattle because of the large aggregations of winged adults and wingless nymphs that they form on trees with lichen growth. They feed on the lichens, and they do not damage the trees. Though we are responding to you on the day you submitted your request, we will not be posting your submission until mid-June while our editorial staff is away from the office.

Thank you Daniel! I did look at your description of Barklice earlier, but just wasn’t sure. So glad I asked. Thank you for your quick response.
Have a good weekend.
Loretta

Related posts:

Subject: Mystery bugs
Location: St Petersburg, FL
April 10, 2016 5:30 pm
Hi— while walking my dog the other day I came across a swarming group of insects on the side of a small tree in the early morning, which included the nymphs. When I returned an hour later to take more photos, they had entirely disappeared. I posted a picture on Instagram and many people were interested in knowing what they could be. An online friend had posted a picture from Tennessee that showed the nymphs w/o any adults. I live in the Tampa Bay Area. Do you have any idea what they are? Many thanks for any help you can provide!
Signature: KARBARG

Tree Cattle

Dear KARBARG,
These benign insects are Barklice or Tree Cattle, Cerastipsocus venosus. The feed on lichens and do not harm the trees upon which they are found.

Many, many thanks for identifying them. I spotted three more groups this morning on another oak in the neighborhood. I’m very happy to share this information with my Instagram friends 🙋🏻💕

Subject: On Crepe Myrtle Bark
Location: Auburn Alabama
March 6, 2016 3:37 pm
Found this on crepe myrtle tree whilst pruning today–they traveled together in 20-30 bug groups, moving then stopping on the bark. What is this?
Signature: Bob Alabama

Barklice Carnage

Dear Bob,
These are benign Barklice. Home gardeners may find the presence of aggregations of Barklice or Tree Cattle as they are commonly called, alarming because generally insects found in large groups on plants are injurious, Barklice will not harm your crepe myrtle tree. Barklice feed on lichens on tree bark and fence posts. We hope future encounters do not meet with Unnecessary Carnage because it appears the Barklice in your image have succumbed to pesticide spray.

Subject: Tick-like bug
Location: San Francisco, CA
March 3, 2016 6:46 pm
Hey The Bugman,
Wondering if you can help me id this bug. Sorry, it’s not the best quality pic. One pic is up close, the other is so that you can get an idea of the scale. I found the bug in my back yard on a calla lily. You’ll also see that there’s a smaller bug near it. I’m most curious about the larger bug.
Any ideas?
Thanks!
Signature: StormMiguel

Aphid on a Calla Lily

Dear StormMiguel,
This is an Aphid and we do not believe its diet, which consists of sucking fluids from plants, is limited to the calla lily. The other, smaller insect, appears to be a Psocid.

Aphid and possible Psocid

Thank you so much! I never would have guessed it was an aphid – as big as it was. I was worried it might be a tick.
I will make a donation to your site. Sorry that I can only afford $10 at this time.
Your help is greatly appreciated!

Subject: What is this bug?
Location: Sydney
February 18, 2016 2:03 am
I see it everywhere in our place. On my laptop, spoon drawer, on doors.
It’s cream coloured and very small.
Help appreciated
Signature: Maryam

Booklouse

Dear Maryam,
This is a Booklouse in the family Liposcelididae, probably in the genus Liposcelis. According to BugGuide they are found: “worldwide and across NA; many spp. are now nearly cosmopolitan or otherwise widely spread through agency of man, mostly with stored products.” They are basically harmless to humans, though when they are plentiful, they might render stored foods unpalatable. According to the Penn State Department of Entomology: “Booklice, also called psocids, are not true lice. While they resemble lice in size and shape, booklice feed only on fungi or mold. If you find them in grain or other stored food products, it is an indication of high humidity which encourages mold growth. In addition to food products, psocids may be found under wallpaper, in furniture, along the sides of windows or on window sills around potted plants. Booklice do not bite, transmit disease, or damage food or fabric, but they can be very annoying when present in large numbers.”